Does anything affect your statutory rights?
You've bought a packet of crisps or a box of cereal or a shirt, and the retailer says that if you find a mouse in it, or it dissolves in the wash, then you can return it and that your "statutory rights will not be affected".
You only ever hear about statutory rights not being affected - you never see a sign saying that something does affect your statutory rights.
You generally see the expression in shops or on manufactured goods referring to the returns policy, which is governed by the Sale of Goods Act.
"It's all about getting what you bargained for," says Ron Turner, a lawyer at Buss Murton.
"The main things are that they should last as long as you would expect, and that they are fit for purpose."
So can anything affect those statutory rights?
"Generally not," Ron Turner says.
Then why bother telling everybody that their statutory rights are not being affected?
"It is a very odd expression, it's a fairly stupid thing to say," says Clive Zietman, a lawyer at Stewarts Law.
"It's the loose language that companies use without thinking about the law."
"What they're trying to say is they might do something above what the law demands."
Ron Turner gives the example that if you buy a packet of sausages that taste funny, you return the pack to the manufacturer and they give you your money back and pay for your postage and even give you some vouchers to buy more products, it does not affect your right to sue them if you later get food poisoning from the sausages you ate.
Similarly, just because a manufacturer encourages you to return faulty goods to them for a full refund, it does not detract from your right to return them to the retailer, which would normally be your first port of call.
This is the view taken by United Biscuits, which includes assurances about statutory rights being unaffected on products such as its Jacob's Cream Crackers.
"The reason this happens is that people may be concerned that by returning product they might lose the right to pursue other remedies, the public not necessarily being familiar with consumer legislation," the company's legal team told BBC News.
"Therefore, this is put on pack to make consumers feel more comfortable in coming direct to us on a 'without prejudice' basis."
Julia Durham from Citizens Advice says that under the Consumer Protection from Unfair Trading regulations, if retailers or manufacturers are offering guarantees, they must say that what they are offering is in addition to people's legal rights.
"A lot of retailers offer store policies, trying to be helpful, but they sometimes forget that statutory rights exist as well," she says.
She gives the example of a second-hand car dealer, which offers a free three-month warranty but says it will not help at all after that time.
Under statutory rights, if the car lasts less long than could be reasonably expected, then you can try to get redress from the retailer whatever its policy is.
"Sometimes guarantees seek to take away from statutory rights," she warns.
It is important to remember that the terms and conditions that may apply to a shop offering, for example, to refund a product if you change your mind, which it is not forced to do by law, will not apply to customers returning faulty goods, which are covered by statutory rights.
So is there nothing you could do that would be so extreme that it would affect your statutory rights? Perhaps you could deliberately use forged banknotes to buy that packet of sausages and then try to sue the manufacturer when you got food poisoning.
"If you were guilty of a criminal offence, you might lose your statutory rights," Mr Zietman says.
"The contract would be voided by illegality, so your statutory rights would disappear."
Mr Turner agrees that "some judges in some courts may feel that barred you from making a claim".
Ms Durham points out that in order to have statutory rights, you have to prove that the transaction took place, perhaps with a receipt or credit card statement.
What that means is that if you pay with cash and lose your receipt, that may affect your statutory rights.
So it turns out that there may be some things you can do that will affect your statutory rights.
It's funny that you are never warned about them!